Photocatalytic degradation of thimerosal in human vaccine's residues and mercury speciation of degradation by-products

New Insights on the UV/TiO2 Photocatalytic Treatment of Thiomersal and its 2-Sulfobenzoic Acid Product

“…S1 in the supporting information section (SI)). This is in agreement with the results of Yepsen et al [11], who reported for TM two absorption bands in the UV-C range (233 and 263 nm), and no photolysis of the compound when using a UV-A lamp in the absence of a photocatalyst. Other studies [26][27][28] indicate that high energy UV irradiation is needed for an efficient TM photolysis.…”

“…Previous works were conducted on the TiO 2 photocatalytic inorganic mercury(II) reduction under UVA light and even under solar light [5,[29][30][31][32][33][34]. The TiO 2 photocatalytic treatment of organomercurial compounds is scarce, phenylmercury [35,36], methylmercury [37,38], ethylmercury [39] and TM [11,40] being the only studied systems reported in the literature. In all cases, and depending on the conditions, Hg(0), HgO, and/or calomel (Hg 2 Cl 2 ) were deposited on the photocatalyst.…”

“…In particular, for TM, Yepsen et al [11] studied TiO 2 heterogeneous photocatalysis (pH 2 and 0.2 g L −1 TiO 2 , N 2 bubbling) under UV-A in the presence of formic acid as a sacrificial agent. Dissolved Hg(II), Hg(0), salicylic acid, and other intermediate oxidation products were found; all organic compounds were finally mineralized.…”

Liquid chromatography coupled to molecular fluorescence with postcolumn UV sensitization for thimerosal and derivative compounds monitoring in environmental samples

“…In our case, we used formic acid, based on a work of Yepsen et al. that performed a catalytic photodegradation of THM by UVA in presence of TiO 2 nanoparticles with HCOOH as “sacrifice” reagent.…”

“…HPLC with UV detection, on the contrary is a “low cost” substitute, but the affordable detection limits are not compatible with environmental levels of THM and its derivatives. Alternatively, absorption spectra can be sensitized photochemically through UV irradiation of samples . The alternative of using molecular fluorescence (MF) as detection is an attractive approach to the above mentioned, but the low fluorescence of THM and its derivatives requires adding a fluorophore, or other approaches for reconfiguration of molecules aiming to generate new electronic configurations with more π‐electrons .…”